In ecological psychology, affordances are relations between features of the environment and the abilities of an animal, where an ability is a functional property relevant to an animal’s behavioral ecology because it was evolutionarily useful (@2003chemeroOutline). Affordances were introduced to explain the immediate content of perceptions, which are broadly defined as relations between a perceiver and what is being perceived, by making action inherent in perceptual experience. On this view, when I see a chair, I do not perceive a thing that has four legs and has a surface parallel to the ground, etc., but something that affords sitting.
Affordances have two key ontological properties:
- Nonphysical but real: like the relation of “being taller than,” affordances are not physical things in the world, but nonetheless perceivable and real.
- Normative, not deterministic: in contrast to dispositional properties, which unambiguously manifest when paired with an actualizing circumstance (e.g., “being fragile”), affordance relations reflect functional properties that merely say how individuals with abilities are supposed to behave—and they may fail to do so. For example, I may see a stair as something that affords stepping on but end up tripping over my own foot when I go to execute the action.
References
- Gibson (1979). The Ecological Approach to Visual Perception
- @2003chemeroOutline, “An outline of a theory of affordances”